Plate Element for a Plate Cooler

ABSTRACT

The invention relates to a plate element for a plate cooler, comprising an outer border ( 8   a ), running at least partly around the plate element and lying substantially in one plane, the outer border ( 8   a ) forming an upper termination of a peripheral side wall ( 8 ), a base ( 1 ), lying in a bottom plane, with a plurality of openings ( 2, 3 ) for allowing a medium to pass through, at least one first opening ( 2, 3 ), formed as an aperture in the base, and at least one second opening ( 4, 5 ), an opening rim ( 4   a,    5   a ) of the second opening running in a plane which is parallel to the bottom plane and is offset in a vertical direction with respect to the bottom plane. A plate element is created according to the invention by the second border delimiting at least certain portions of a support area ( 6, 7 ) which is substantially parallel to the bottom plane ( 1 ), the support area ( 6, 7 ) running at least from the second opening ( 4, 5 ) to the side wall ( 8 ) and being offset with respect to the base in a vertical direction in relation to the bottom plane.

The present invention relates to a plate element for a plate cooler as claimed in the preamble of claim 1 and to a plate cooler comprising a plurality of constructionally identical plate elements as claimed in any one of claims 1 to 8.

Plate coolers in which a number of usually constructionally identical plate elements arranged in alternation are arranged one above another are known in the art, two separate systems of chambers being formed, a first heat-transferring medium flowing through one chamber system and a second medium through the other chamber system. Generally, this gives rise to the problem of optimizing the flow paths of the media within the chambers, thus providing, for a given overall size and number of plates, exchange of heat between the two media that is as advantageous as possible.

DE 199 39 264 A1 describes a plate heat exchanger in a stacking design in which a plurality of identical plate elements are secured to one another and soldered to one another along a conical outer edge. The plate elements each have four substantially circular openings within a bottom region of the plate element, two of the circular openings each having a beveled edge. Each of the beveled edges is set apart from the outer edge. Stacking of the plate elements produces in the regions between the outer edge and the bevels of the openings a considerable volume containing a heat-conveying medium having a particularly low flow speed. Firstly, this adversely influences the effectiveness of the heat exchanger for given dimensions. Secondly, such regions of tightly packed medium allow the deposition of entrained particles and agglomeration to form bulky deposits. Spontaneous detachment of relatively large deposits of this type can damage an overall system, for example if the heat exchanger is an oil cooler of a motor vehicle engine.

The object of the invention is to disclose a plate element for a plate cooler, allowing the production of a plate cooler having improved effectiveness and deposition resistance.

According to the invention, for a plate element mentioned at the outset, this object is achieved by the characterizing features of claim 1.

This configuration, in particular the support area running between the side wall and the second opening edge, allows a particularly small proportion of heat-carrying medium to be present in a low-flow region of a plate cooler. Regions between the outer edge of the plate cooler and media openings that are disadvantageous, in particular, with regard to the flow of media are reduced or eliminated, so the medium is present mainly between the openings and thus in its main flow regions. Overall, the same exchanger power can thus be achieved in the case of a smaller media volume present in the plate cooler. This allows a plate cooler to be, in particular, lighter and more compact in its configuration.

In the interest of simple production of a plate cooler, the plate element can in a preferred embodiment be connected to a second constructionally identical plate element, the support area of the plate element abutting the second plate element substantially two-dimensionally in the connected arrangement. The constructionally identical configuration of the second plate element allows a plate cooler to be produced particularly economically.

Also preferably, the plate element is in this case two-dimensionally soldered to the second plate element, at least in the region of the two-dimensional abutment. In contrast to the substantially linear soldering which is known in the art and is provided by in principle one-dimensional configuration of the edges, a much larger contact area of adjacent plate elements of a plate cooler can be soldered in the case of a plate element according to the invention, thus providing overall particularly high strength and particularly high long-term stability with respect to cracks and leakages which occur.

In a preferred embodiment of a plate element according to the invention, at least one of the openings has a non-circular shape extending in a longitudinal direction. This allows in a simple manner the medium to flow in a particularly broad range through a plate cooler consisting of plate elements according to the invention. The aforementioned two-dimensional abutment or two-dimensional soldering, in particular, provides a secure connection of plate elements having non-circular openings.

In a preferred embodiment, a plate element according to the invention has a profile, the profile being arranged in a flow path for influencing the flow of the medium. A profile of this type allows the distribution of the medium flow over the plate element to be improved for the purposes of optimizing the power of the exchanger. In the interest of simple production, the profile is preferably configured by embossing or deformation of the base of the plate element.

Particularly preferably, the profile is in this case undulatory, a plurality of points of contact of the profiles being present between the profile of the plate element and the profile of a constructionally identical second plate element which is secured to the first plate element. In this way, the flow of medium can be guided by the profile in a particularly targeted manner.

In the interest of simple production, the plate element can, as a whole, be produced from a metal plate of constant thickness. The plate element can in this case be shaped from the metal plate of constant thickness by means of processes known per se, for example by means of deep-drawing, drop-forging or other methods. The material of the metal plate is preferably an aluminum alloy in order to allow overall a light design of a plate cooler.

A plate cooler according to the invention comprises a plurality of constructionally identical plate elements as claimed in any one of claims 1 to 8. This combines the advantages of the configuration of the plate element according to the invention with cost-effective large-scale production of a plate cooler.

Further advantages and features will emerge from the exemplary embodiment described hereinafter and from the dependent claims.

A preferred exemplary embodiment of a plate element according to the invention and of a plate cooler will be described hereinafter in greater detail with reference to the appended drawings, in which:

FIG. 1 is a spatial view from below of a plate element according to the invention, a conical peripheral edge protruding into the plane of the drawing;

FIG. 2 is a spatial view from above of the plate element from FIG. 1, the peripheral edge projecting out of the plane of the drawing;

FIG. 3 is an enlarged view of a detail of the plate element from FIG. 1;

FIG. 4 is a cross section through four plate elements according to FIG. 1 that are stacked one on top of another in alternating orientation and form, as a whole, a portion of a plate cooler;

FIG. 5 is a detailed view of a cross section through an individual plate element according to FIG. 1; and

FIG. 6 is a plan view onto a modification of the plate element from FIG. 1, a separate turbulence insert being provided instead of embossed profiles.

The plate element according to FIG. 1 comprises a bottom plane 1 having two openings 2, 3 of a first type that are located opposite each other in the direction of flow of a medium and both have an edge 2 a, 3 a lying in the bottom plane 1. The two first openings 2, 3 are each elongate in their configuration, a longitudinal diameter of the openings 2, 3 forming somewhat more than 1.5 times a transverse diameter. The medium flows perpendicularly to the longitudinal direction of the openings 2, 3. The plate element 1 has in the plan view a rectangular shape with markedly rounded corners. The two first openings 2, 3 are both arranged on the same longitudinal side in the corner regions of the rectangle.

Two openings 4, 5 of a second type, which have the same shape and opening width as the first openings 3, 4, are provided on the opposing longitudinal side. However, the edges 4 a, 5 a of the second openings 4, 5 are not arranged in the height of the bottom plane 1 but rather lie in a plane parallel to the bottom plane 1. There also lie in this plane support areas 6, 7 of the plate element that are respectively associated with the openings 3, 4, extend parallel to the bottom plane 1 but are arranged offset in the direction of the vertical axis of the plate element. The vertical axis is defined as being perpendicular to the plane of the drawing in FIG. 6. The openings 3, 4 are formed in the present case as simple apertures in the support areas 6, 7. However, they can also be beveled or differ in a different manner from a simple cutout in the support area.

The support areas 6, 7 are delimited partly by a respectively rounded edge 6 a, 7 a of the bottom plane 1 and, at the level of the support areas 6, 7, partly by a rounded projection 8 b of a side wall 8 encircling the plate element. The side wall 8 fully encircles the plate element and has an outer edge 8 a, all of which lies in the same plane. In addition, this side wall 8 is not arranged at right angles to the bottom plane 1 but rather just slightly outwardly inclined, so overall it has a conical arrangement. This allows a plurality of constructionally identical plate elements to be stacked one inside another, the outer edge 8 a resting in each case at a certain height of the side wall 8 of the nearest plate element and being soldered thereto at this location (see FIG. 4).

The support areas 6, 7 extend in each case from the projection 8 b of the side wall 8 to the edge 4 a, 5 a of the second openings 4, 5. The projection 8 b is located in the region of the support areas 6, 7 not at the same height as in the region of the base 1, thus producing steps 8 c in the course of the projection 8 c. As the stacked illustration according to FIG. 4 shows, the two-dimensional abutment of a support area 6, 7 against the base 1 of the subsequent plate element, which is arranged rotated through 180°, produces a two-dimensional soldered joint which is particularly stable and secure with respect to leakages occurring during the operating period.

As FIG. 4 illustrates, the alternating arrangement and sealing soldering of a plurality of plate elements forms a portion of a plate cooler comprising a first system A and a second system B of chambers. In this case, a first heat-carrying medium, for example water and/or glycol, flows through the first system A in each case from one plate opening to the other, perpendicular to the plane of the drawing in FIG. 4, and a second heat-carrying medium, for example engine oil, flows through the second system B in each case from one plate opening to the other, perpendicular to the plane of the drawing in FIG. 4.

The plate element according to the invention can be produced by way of a conventional shaping process, a blank being a simple plate of constant thickness made of an aluminum alloy.

The preferred plate element according to FIG. 1 to FIG. 5 additionally has a profile 9 of the bottom plane 1. This profile comprises substantially a plurality of zigzag or undulating recesses which each form a continuous channel and are embossed from below into the base 1 of the plate element. Each of the zigzag channels 9 crosses a notional flow path of the medium that runs in each case from one short side of the plate element to the opposite short side of the plate element. The channels 9 are additionally positioned in such a way that stacking of constructionally identical plate elements produces as large a number as possible of intersections of channels 9 of one plate element with channels 9 of the other plate element. Points of contact of the adjacent channels 9 are present at these intersections, and this is ensured by corresponding configuration of the embossing depth thereof. Preferably, the plates are soldered to one another at the contact points.

Overall, this provides purposeful deflection and swirling of the flowing medium, and this helps to optimize the capacity of the heat exchanger.

In a modification according to FIG. 6, the plate element is configured identically to the exemplary embodiment according to FIG. 1 to FIG. 5 except for the profiles 9, a turbulence insert 10, which is hatched in FIG. 6, being provided on the plate element instead of the profiles 9. Turbulence inserts 10 of this type for improving the heat exchanger power are known per se in the art, and merely the customized form thereof is adapted to the plate element according to the invention.

All of the drawings are to scale, so dimensional ratios can, if appropriate, be inferred therefrom. 

1. A plate element for a plate cooler, comprising an outer edge at least partly encircling the plate element and lying substantially in one plane, the outer edge forming an upper termination of a peripheral side wall, a base lying in a bottom plane, at least one first opening configured as an aperture in the base, for allowing a medium to pass through, and at least one second opening an opening edge of the second opening running in a plane which is parallel to the bottom plane and is offset in a perpendicular direction with respect to the bottom plane, wherein characterized in the second edge delimits at least certain portions of a support area which is substantially parallel to the bottom plane, the support area running at least from the second opening to the side wall and being offset with respect to the base in a perpendicular direction in relation to the bottom plane.
 2. The plate element as claimed in claim 1, wherein the plate element can be connected to a second constructionally identical plate element, the support area of the plate element abutting the second plate element substantially two-dimensionally in the connected arrangement.
 3. The plate element as claimed in claim 2, wherein the plate element is two-dimensionally soldered to the second plate element, at least in the region of the two-dimensional abutment.
 4. The plate element as claimed in claim 1 wherein at least one of the openings has a non-circular shape extending in a longitudinal direction.
 5. The plate element as claimed in claim 1, wherein the plate element has a profile, the profile being arranged in a flow path for influencing the flow of the medium.
 6. The plate element as claimed in claim 5, wherein the profile is configured by embossing the base of the plate element.
 7. The plate element as claimed in claim 6, wherein the profile is formed by a turbulence insert.
 8. The plate element as claimed in claim 5, wherein the profile is undulatory, a plurality of points of contact of the profiles being present between the profile of the plate element and the profile of a constructionally identical second plate element which is secured to the first plate element.
 9. The plate element as claimed in claim 1, wherein the plate element can, as a whole, be produced from a metal plate of constant thickness.
 10. A plate cooler comprising a plurality of constructionally identical plate elements as claimed in claim
 1. 